So you have funded an address that belongs to a core wallet you own, but don't have the diskspace to do a full sync?
Then i'm happy to tell you the following: you don't need to do a full sync!
Just run the core wallet, and while it's syncing export the private keys belonging to the address you funded => import those private keys in an SPV wallet (like electrum, but make sure you download from the official repo + check the signatures) => then just spend the unspent output yourself
Faaaaar less risk than sharing your walletfile!